Dynamics Flashcards
What are the types of forces
- Contact forces
- Non-contact forces
Define mass
Mass is the amount of matter in a body
Define weight
Weight is the gravitational force acting on an object that has mass
What are the effects of a resultant force on the motion of a body
- Body at rest moves
- Moving body increases speed
- Moving body decreases speed
- Moving body changes direction
What is Newton’s Second Law of motion
Newton’s Second Law of motion states that acceleration of an object is directly proportional to the net force acting on it and is inversely proportional to its mass
Define inertia
Inertia of an object is the reluctance of the object to change its state of rest or motion due to its mass
Define a gravitational field
A gravitational field is a region in which a mass experiences a force due to gravitational attraction
What is Newton’s First Law of motion
Newton’s First Law of motion states that every object will continue in its state of rest or uniform motion in a straight line unless a resultant force acts on it
What is Newton’s Third Law of motion
Newton’s Third Law of motion states that if body A exerts a force AB on body B, then body B will exert an equal and opposite force BA on body A
What are the pair of equal and opposite forces called
Action reaction forces
Define friction
Friction is the contact force that opposes or tends to oppose motion between surfaces in contact
Define terminal velocity
Terminal velocity is when air resistance equals the weight of the falling object such that there is zero acceleration and object falls with constant velocity
What are the factors affecting terminal velocity
- Larger weight = larger terminal velocity
- Larger surface area = smaller terminal velocity
How do objects fall with air resistance
- Air resistance increases as speed of falling object increases
What happens when there is a net force acting on an object initially at rest
Object has uniform acceleration
What happens when balanced forces applied to object initially moving with constant velocity
Object continues moving at same constant velocity
What happens when net force applied to object initially moving with constant velocity
Object has uniform acceleration
What happens when net force against direction of initial motion applied to object initially moving at constant velocity
- Object has uniform deceleration in same direction of initial motion
- Stops instantaneously
- Uniform acceleration in direction of net force
